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zipcodes.pro — CITY/MD/SAN-MAR

San Mar ZIP codes, Maryland

No ZIP code is named for San Mar, MD; addresses there use a neighbouring town's name. The ZIP code covering it is 21713. Its area codes are 240, 301 and 227.

USPS city name
0 ZIP codes
Overlapping the city
1 more
Population
306
Area codes
240, 301, 227

NANPA lists no telephone rate centre for San Mar itself, so these are the area codes of the nearest one, Hagerstown (3.7 miles). A town on an area-code boundary can differ from its neighbour.

San Mar in numbers

About 306 people live in San Mar, in 117 households. The median owner-occupied home is valued at $240,500 (43% below the Maryland median), and median gross rent is $616 a month. The median age is 79.4; 12.0% of adults 25 and over hold a bachelor's degree or higher (43.4% across Maryland).

Population306San Mar306
Households117San Mar117
Median age79.4San Mar79.4Maryland39.4US 38.9
Median home value$240,500San Mar$240,500Maryland$419,900US $332,700
Median gross rent$616San Mar$616Maryland$1,705US $1,413
Bachelor's degree or higher12.0%San Mar12.0%Maryland43.4%US 35.7%
Population density657 / sq miSan Mar657 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place San Mar CDP. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes covering San Mar

These ZIP codes cover part of San Mar but are addressed as somewhere else.

ZIP codes overlapping San Mar
ZIP City Type Population Median income Median home
21713 Boonsboro , MD Standard 9,846 $96,199 $369,200

Map of San Mar ZIP codes

21713

The ZIP codes of San Mar, MD, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near San Mar

The nearest larger towns are Mount Lena (391 people, 1.0 mi), Mapleville (365 people, 1.2 mi) and Beaver Creek (439 people, 2.1 mi).

Towns near San Mar
TownPopulationDistance
Boonsboro 3,809 3.1 mi
Robinwood 8,042 5.3 mi
St. James 4,824 5.9 mi
Hagerstown 43,665 7.5 mi
Smithsburg 3,115 7.8 mi
Halfway 10,849 8.2 mi
Paramount-Long Meadow 2,569 9.2 mi
Middletown 5,014 9.5 mi
Fountainhead-Orchard Hills 6,567 10.2 mi
Maugansville 3,624 11.3 mi
Braddock Heights 2,892 12.6 mi
State Line, PA 3,111 13.3 mi
Thurmont 6,254 13.3 mi
Jefferson 3,314 14.0 mi

More nearby: every ZIP code in Washington County · Maryland ZIP codes

Cite this page

zipcodes.pro. “San Mar, MD ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/md/san-mar

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